Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already indicate non-read-only, non-idempotent, non-destructive. The description adds bulk support but no details on update semantics (e.g., partial vs. full update, whether data merges or replaces, side effects). The mention of anonymize being irreversible is irrelevant to this tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is not concise because it includes a list of actions that are not relevant to this tool (create, anonymize, create_etickets) before the flattened action note. This wastes space and muddies the message.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool with no output schema and no annotations describing behavior, the description is severely lacking. It does not explain what happens on update, how to construct data, whether updates are idempotent, or any edge cases. The bulk support is the only concrete addition.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, so the description must explain parameters. It maps id and data to update, and ids for bulk, but does not explain the 'account' parameter. It also does not clarify the structure or constraints of 'data', leaving significant gaps.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description lists multiple actions (create, update, anonymize, create_etickets) but then states '[Flattened action: update]', creating ambiguity about whether this tool handles all or only update. The name clearly indicates update, but the extra actions confuse rather than clarify.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance on when to use update versus the sibling tools (guru_contacts_write_create, guru_contacts_write_anonymize, etc.). It mentions bulk support but gives no context on when bulk is appropriate or any prerequisites.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.